1: Introduction Flashcards
What can germinal centres in the iris look like?
Brown spots
What is the cause of a lipid ring in the eye?
High cholesterol, e.g. hypothyroidism or old age
What is a tigroid fundus?
Fundus pigmented like tiger
What can distant direct opthalmoscopy see?
Pupil size, strabismus, cataract
What does a cataract look like on distant direct ophthalmoscopy?
Black opacity
What dioptre is distant direct opthalmoscopy?
0
What can you see on direct opthalmoscopy?
Fundus, cataract, adnexa
What dioptre for fundus on direct opthalmoscopy?
0
What dioptre for cataract on direct opthalmoscopy?
10
What dioptre for adnexa on direct opthalmoscopy?
20
What are the two types of indirect loupe lens?
Monocular or binocular
When are indirect loupe lenses used?
Wider field of view so used to screen retinas
What kind of image does an indirect loupe lens give?
Inverted
What does gonioscopy measure?
Iridocorneal angle
How do you perform a Schirmer tear test?
In for one minute plus or minus anaesthetic
What is normal tear production?
10-20mm/min
What is classed as dry eye?
Below 5mm/min
When would you expect a high Schirmer tear test?
Irritated eye e.g. ulcer (over 18mm/min)
What are the three types of tonometer?
Indentation, applanation, rebound
What is a normal IOP?
15-20mmHg
What happens to the IOP in inflammation?
Low (10mmHg) because PGs open new drainage pathways in ciliary body
What does Rose Bengal do?
Adheres to areas deficient in mucus (e.g. dry eye)
What is the limbus?
The edge of the iris
What does the eye begin as embryologically?
The optic vesicle with overlying ectodermal placode
What does the placode develop into?
Cornea and lens
Which structures come from neural crest and mesenchyme?
Corneal stroma and epithelium, IC angle structure, neural ganglia, anterior segment vascularisation
What normally happens to the blood vessels after supporting growth?
Apoptose
What happens if blood vessels fail to apoptose?
Persist as membrane
What can happen to macrophages in FIP?
Clump - “mutton fat”
